Worldwide, malignant melanoma was responsible for an estimated 49,100 deaths in 2010, yet when detected at the earliest (in situ) stage, there is no change in life expectancy. Thus, early detection of malignant melanoma is critical. In private practices throughout the USA, patients are appearing in clinics with smaller, earlier lesions, before the classic features of melanoma have become fully apparent. In one study, 21% of melanomas in situ were smaller than 6 mm in greatest diameter.